BREAKING: Heckler & Koch HK237 and HK337 in .300 Blackout / Whisper, RUAG producing ammunition

    BREAKING NEWS from Nürnberg, Germany: H&K is manufacturing rifles chambered in .300 Blackout / Whisper. The doors to the Enforce Tac expo literally just opened minutes ago (at time of writing) and as we walked in we were surprised to see the new HK237 and HK337 chambered in .300 AAC Blackout / .300 Whisper. The new HK carbines are displayed together with new .300 BLK ammunition manufactured by RUAG.

    .300 Whisper is a CIP standard cartridge, developed in the early 1990s by J.D. Jones of SSK Industries and .300 AAC Blackout (.300 BLK) is a SAAMI standard cartridge developed by Remington based on the .300 Whisper.

    RUAG’d new .300 Whisper load was developed in co-operation with B&T (CH) and it tests well out to 300 meters. They wrote …

    At an operative range of approx 150m, special police and military units use the powerful .300 Whisper primarily in urban areas against secondary targets such as alarm systems, fighting dogs or cameras.The deformation ammunition .300 Whisper SWISS PHV Styx Action (HV=High Velocity) widens the application spectrum and provides highly precise hits also at 300m. The range of ammunition enables the shooter to move from subsonic to supersonic by a magazine change within seconds in order to remain efficient and convertible.

    The lighting condition at this exhibition made is almost impossible to take good photos, so please excuse the quality….

    Photo by Jan-P. Weisswange

    Unfortunately there is not much more information available at this time. H&K are good at the strategy of displaying first and releasing the information at a later stage, which is frustrating for fact-seekers.

    My conclusion: The new HK carbines look like HK416 and G36, but re-barreled to accommodate new calibers. If there’s more to it I’m sure we’ll find out soon.

    UPDATE 1+2:

    The below pictures are courtesy of Frag Out Magazine and Soldier Systems.

    HK237 (G36 variant). There’s so much I want to write about the ergonomics of this stock… What is going on there?

    HK237 Close-up …

    Helmet stock.

    Fully automatic.

    The HK337 – looks like a HK416 but the caliber is on steroids, .300 Blackout or .300 Whisper….

    HK337 Close-up…note the serial.

    Very compact, fully automatic.

    Bonus picture below: HK433. Still in 5,56×45 mm, but there are rumors about a .300 Blackout / Whisper version as well.



    Eric B

    Ex-Arctic Ranger. Competitive practical shooter and hunter with a European focus. Always ready to increase my collection of modern semi-automatics, optics, thermals and suppressors. TCCC Certified. Occasionaly seen in a 6×6 Bug Out Vehicle, always with a big smile.